Mandrel-less Launch Toe Initiation Sleeve (TIS)

ABSTRACT

The present invention is a valve tool utilized for hydraulically fracturing multiple zones in an oil and gas well without perforating the cement casing. An oil/gas well completion method involves the use of a valve that is installed as part of the casing string of the well. A mandrel-less casing provides for cement flow within the casing when the valve element is in a closed position and allows for axial flow of fracturing fluid through the cement casing to fracture the formation near the valve when the sleeve is open. The invention disclosed herein is an improved valve used in this process.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a continuation-in part of application Ser. No.14/487,772, filed Sep. 16, 2014, entitled Mandrel-less Launch ToeInitiation Sleeve (TIS), which claims the benefit of U.S. ProvisionalApplication 61/878,115, filed Sep. 16, 2013, each application of whichis incorporated herein by reference. This application also claims thebenefit of U.S. Provisional Application 61/907,452, filed Nov. 22, 2013,entitled Launch Toe Sleeve, which is also incorporated herein byreference.

BACKGROUND OF THE INVENTION

The present invention is directed to a valve utilized for hydraulicallyfracturing multiple zones in an oil and gas well without pre-perforatingthe cement casing. An oil/gas well completion method involves the use ofa valve that is installed as part of the casing string of the well. Amandrel-less casing provides for cement flow within the casing when thevalve element is in a closed position and allows for axial flow offracturing fluid through the cement casing to fracture the formationnear the valve when the sleeve is open. The invention disclosed hereinis an improved valve used in this process.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a cross-sectional view of a valve tool according to at leastone aspect of the current invention with the sleeve closed.

FIG. 2 is a cross-sectional view of a valve tool according to at leastone aspect of the current invention with the sleeve opened.

FIG. 3 is an exploded, cross-sectional view of a valve tool according toat least one aspect of the current invention.

FIGS. 4-8 are cross-sectional views of the various parts of the tool.

FIGS. 9-11 are cross-sectional views of the top and bottom subs and thesleeve.

FIG. 12 is a cross-sectional view of the valve tool according to atleast one embodiment of the invention.

FIGS. 13-14 show an additional embodiment of the invention having portplugs through the mandrel wall.

Similar reference characters denote corresponding features consistentlythroughout the attached drawings.

SUMMARY OF THE INVENTION

The present invention is directed to a valve utilized for hydraulicallyfracturing multiple zones in an oil and gas well without perforating thecement casing. A mandrel-less casing provides for cement flow within thecasing when the valve element is in a closed position and allows foraxial flow of fracturing fluid through the cement casing to fracture theformation near the valve when the sleeve is open. The inventiondisclosed herein is an improved valve used in this process.

It is therefore an object of the invention to provide a mandrel-lesscasing for providing cement flow within the casing.

It is an object of the invention to provide a casing having a sleevewithin the casing that protects openings in the casing from being incommunication with cement during the cementing in process.

It is an object of the invention to provide the casing with a moveablesleeve that can be moved by pressure or other devices to expose thewindows/opening/ports in the casing to prepare for the fracking process.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT(S)

The present invention is to a mandrel-less valve tool 10 having an upperand lower sub 12, 14. Each sub preferably has an extended cylindricalportion which acts as a cement barrier in conjunction with sleeve 16 topresent a smooth, nearly continuous wall from one end of the tool 10 tothe other.

An upper body 18 and lower body 20 are provided about the upper andlower subs. The upper and lower body thread together or may be pinnedtogether by a pin or a screw 19 and then to the subs to locate the subsrelative to each other by set screws 21 or the like. Alternatively,upper body 18 and lower body 20 could be formed as a single unit. A gap22 between the subs of a predetermined size provides a window or openingthat aligns with an opening 24 in the upper body so that fluid mayselectively be passed between the interior of the tool 10 and theenvironment about the tool during fracking.

An upper end 30 of sleeve 20 abuts a collar 32 (FIG. 3) to form a sleevechamber between the upper end 30, the collar 32 and upper body 16. Anopening through the upper sub is selectively blocked by a burst disk 34.An optional access port 36 may be blocked by a pipe plug or the like forreplacing or repairing the burst disk 34 or to allow equalization of thepressure within the sleeve chamber while the tool is being assembled.The sleeve chamber is originally at atmospheric pressure, i.e., isunpressurized. During operation, as will be discussed further hereunder,a high pressure within the upper sub will burst the burst disk 34causing an increase in pressure on the upper end 30 of the sleevebiasing the sleeve to move downwardly. The sleeve is preferablyprevented from moving unintentionally by shear pins, a shear ring or thelike, which may be provided between the lower body and the sleeve at 37or at other locations (FIG. 3). O-rings or other seals at the samelocations 38,40,42 may also be provided to seal the sleeve chamber. Oncethe pressure in the sleeve chamber is sufficient to overcome the forceof the shear pins, the sleeve will slide downwardly (into chamber 13)exposing window 24 to the interior of the valve tool 10. Movement of thesleeve will be stopped as the lower end 44 of the sleeve strikes thecollar 46 of the lower sub 14. Ratchets, lock rings or other devices maybe used to ensure that the sleeve cannot travel in the reverse directionand cannot close the opening once opened. The chamber 13 may be boundedat one end by piston 15 for known purposes.

In operation, the valve tool is attached onto a casing string at thedesired location. The string is then lowered into a well bore. When thestring is set to a desired depth, cement is pumped through the casingand out into the well bore using appropriate tools or openings. A plugor other device is then lowered through the casing to wipe the casing toremove residual cement. Because the walls of the interior are smooth(i.e., do not include exposed windows or apertures in a mandrel, etc.),the plug can readily remove any cement. When the sleeve 20 is closed,the upper and lower subs present extended cylindrical walls to the plug,and the sleeve 20 provides a cylindrical cover bridging across the gap22 between the upper and lower sub. This is in distinction to prior artdevices, such as the mandrel openings 23 of U.S. Pat. No. 8,267,178,issued Sep. 18, 2012 to Sommers et al., which is incorporated herein byreference. Since the openings are exposed to the interior of the toolwhen the cement is being pumped through the casing, it is possible forcement to creep into the openings in the mandrel of the prior artdevice, and for a plug to be unable to remove the cement from theseopenings, reducing the effective area of the openings.

When it is desired to open the window of the valve tool 10, the pressureis increased in the casing. The increased pressure causes burst disk 34to breach allowing pressure into the sleeve chamber. The pressure insleeve chamber acts downwardly on sleeve 20. The downward pressure at adesired force level shears shear pin or shear ring 37 allowing thesleeve to move out of alignment with gap 22. As the sleeve retreats, thegap 22 is exposed to window 24 of the upper body 16. With the openingsaligned and the sleeve withdrawn, the interior of the valve tool 10 andthe exterior foundation adjacent the valve tool are brought into fluidcommunication. Fracing fluid can then be applied from within to areaoutside the valve tool 10 to fracture the foundation adjacent the valveor to perform other such operations as necessary.

Alternate Embodiment(s)

FIGS. 13-14 show an alternate embodiment of the invention. A valve tool110 is shown having a number of ports plugged by burst discs 124. Thediscs are threaded, interference fit or otherwise attached to the valvetool to selectively provide openings in the mandrel wall when frackingoccurs. The disc protect the interior of the tool prior to fracking. Thediscs may be removed from the mandrel by being exposed to sufficientinterior pressure.

In operation, the pressure is increased in the upper sub by for examplepumping additional fluid pressure into the interior of the tool from anupstream source (not shown). The pressure causes the burst disc 134 toburst allowing the pressure within the mandrel to increase the pressurein the chamber 117 above the sleeve 122. The additional pressure causesthe sleeve 122 to slide down shearing shear ring 132 and sliding intochamber 114. This movement of the sleeve exposes the burst disc coveredports 124 to the interior pressure in the mandrel 116. Once the sleeveis open fracking or other process may be performed to allow fluid insidethe casing and on areas outside the casing (“open hole”).

While this invention has been described as having a preferred design, itis understood that it is capable of further modifications, uses and/oradaptations of the invention following in general the principle of theinvention and including such departures from the present disclosure ascome within the known or customary practice in the art to which theinvention pertains and as maybe applied to the central featureshereinbefore set forth, and fall within the scope of the invention andthe limits of the appended claims. It is therefore to be understood thatthe present invention is not limited to the sole embodiment describedabove, but encompasses any and all embodiments within the scope of thefollowing claims.

I claim:
 1. A well valve tool for providing a window to the environmentaround the valve tool, the tool comprising: a top sub and a bottom sub,wherein said top sub is not connected directly to said bottom sub; anouter sleeve connected between said top sub and said bottom sub havingat least one window port; sealing said window port with a burst disc; aninner sleeve connected between said top sub and said bottom sub withinsaid outer sleeve to define an inner passage way selectively preventingfluid communication between an area within said top sub, bottom sub andinner sleeve with said outer sleeve at least one window port.
 2. Thewell valve tool of claim 1, wherein said sleeve is selectively slidablealong one of the group of said top sub and said bottom sub toselectively provide fluid communication between said inner passage wayand said outer sleeve at least one window port when said burst disc isburst by pressure within said sleeve.
 3. The well valve tool of claim 1,wherein said sleeve is connected to one of the group of said top sub andsaid bottom sub by at least one shear pin or a shear disc.
 4. The wellvalve tool of claim 1, wherein said sleeve includes a pressure burstvalve for pressurizing said sleeve to cause said sleeve to slide alongone of the group of said top sub and said bottom sub to selectivelyprovide fluid communication between said inner passage way and saidouter sleeve at least one window port.
 5. A method of operating a wellvalve tool comprising: providing a top sub and a bottom sub; connectingan outer sleeve between said top sub and said bottom sub, wherein saidouter sleeve includes at least one window port, said window port beingsealed against fluid flow therethrough by a burst disc; connecting aninner sleeve between said top sub and said bottom sub and within saidouter sleeve to selective seal said outer sleeve from an area definedwithin said top sub, said bottom sub and said inner sleeve.
 6. Themethod of operating a well valve tool of claim 5, further comprising:running said valve tool within a well; pouring cement within said valvetool; removing said cement from said valve tool by moving a plug throughsaid valve tool.
 7. The method of operating a well valve tool of claim5, further comprising: running said valve tool within a well; pouringcement within said valve tool; removing said cement from said valve toolby moving a plug through said valve tool; pressurizing the inner passageof said valve tool; said pressure operating to move the inner sleeverelative to said outer sleeve to allow fluid communication between theinner passage and said outer sleeve; said pressure further operating toburst the burst disc to open said window port to allow fluid flowthrough said window port; pumping fracking fluid through said at leastone window port of said outer sleeve.
 8. The method of operating a wellvalve tool of claim 5, further comprising: running said valve toolwithin a well; pouring cement within said valve tool; removing saidcement from said valve tool by moving a plug through said valve tool;providing a pressure burst valve between said inner passage and an innersleeve actuation chamber; pressurizing the inner passage of said valvetool; raising said pressure until said pressure burst valve burstsallowing pressurization of said inner sleeve actuation chamber; saidpressure in said inner sleeve actuation chamber operating to move theinner sleeve relative to said outer sleeve to allow fluid communicationbetween the inner passage and said outer sleeve.